The present invention is related to a connector shell which is used in a receptacle into which a plug is to be inserted.
A receptacle into which a plug is inserted thereby to establish electrical connection between electronic parts is known. This receptacle is required to be made compact like other electronic parts. Further, the receptacle is surface mounted on a surface of a board by solder reflowing method, in the same manner as the other electronic parts.
A sectional view of a conventional receptacle 100 is shown in FIG. 4. The receptacle 100 includes a connector shell 101 having a substantially rectangular tubular shape in which a plug insertion space is defined. A plug guiding piece 104 is disposed in the plug insertion space, and connecting terminals 105 which are provided on the plug guiding piece 104 can be electrically continued to terminals at a plug side. The connector shell 101 has a shell body 102 and mounting pieces 103 extended from the shell body 102 toward a board 106. The receptacle 100 is mounted on the board 106 by fixing the mounting pieces 103 to the board 106 by soldering.
When the connector shell 101 is fixed by soldering to the board 106, solder must be adhered to the mounting pieces 103. This can be accomplished by heating the mounting pieces 103 up to a solder melting temperature. When this is done, the shell body 102 is also heated together with the mounting pieces 103. During a reflow treatment, more than a required amount of solder 110 may be conveyed to side walls of the shell body 102 along the mounting pieces 103. Represented by marks A in FIG. 4 are the solders 110 which have crept up to the plug insertion space and have been solidified. When this happens, it has been feared that the solidified solders may interfere with the plug to be inserted, and the plug cannot be inserted up to a determined position.
It is necessary to take some countermeasures for reliably preventing the solders from creeping up. As an art for preventing the creeping up of the solders, there has been known such an art that a solder wicking prevention layer is formed above a region to be soldered, thereby to prevent the solder from creeping up higher than the solder wicking prevention layer.
In Patent Document 1, there is disclosed a method for forming a solder wicking prevention zone by applying resin or ceramics having a low wettability with respect to the solder, to a contact part of a connector member.
Moreover, in Patent Document 2, there is disclosed such an art that a soldering region is formed in a terminal part to be soldered, by providing a plating layer of gold to which the solder is likely to adhere, on an under layer of nickel, and further, a laser beam is irradiated to an upper part of this soldering region thereby to form a layer of nickel and gold alloy having a low wettability with respect to the solder, and thus, a solder creeping prevention region is formed.
[Patent Document 1] Japanese Patent Publication No. 2006-246424
[Patent Document 2] Japanese Patent Publication No. 2005-243468